Exxon Mobil president and CEO Rex Tillerson is the latest frontrunner to be the next U.S. secretary of state. On Saturday several news organizations — all citing unnamed sources close to President-elect Donald Trump’s transition team — said an announcement on Tillerson’s selection could come soon.

The Trump campaign would not confirm whether a decision has been made, and the president-elect’s communications director tweeted Saturday that no announcement on that Cabinet post would be made “until next week at the earliest.”

Reuters, quoting “a source familiar with the situation,” said Tillerson has not yet been formally offered the position.

Tillerson joins former Trump critic and 2012 Republican presidential hopeful Mitt Romney as the leading contenders for the nation’s top diplomatic post. Former New York City Mayor Rudolph Giuliani was also on Trump’s short list, but he withdrew his name from consideration Friday, citing plans to return to the private sector.

Ties to Russia

Tillerson, chief executive of the world’s largest publicly traded company, oversees operations in more than 50 countries, including Russia. Exxon Mobil reached an oil exploration and production agreement in 2011 with Rosneft, Russia’s largest state-owned oil company. Since 2011, the two companies have formed 10 joint operations in Russia.

In a preview of an interview with Fox News that will air Sunday, Trump, while not confirming Tillerson will get the job, said he would make sense as the choice to be the country’s top diplomat because “he’s a world-class player.”

“He knows many of the players, and he knows them well,” Trump said. “He does massive deals in Russia — for the company, not for himself, for the company.”

In 2013, Tillerson was awarded Russia’s Order of Friendship decoration by President Vladimir Putin.

“If you received an award from the Kremlin ... then, we’re gonna have some talkin’,” Graham told The Washington Post.

Republican Senator John McCain, who called Putin “a thug and a murderer,” has also expressed concerns. He says hearings will be held to address those concerns about Tillerson and his ties to the Kremlin.

“That’s the time to make up your mind as to whether to vote yes or no,” McCain said.

Tillerson's involvement with Russia, including his personal ties to Putin, would most likely draw close scrutiny during any Senate confirmation hearings, given Russia's reported attempts to influence the outcome of November's U.S. presidential election.

One-sided leaks

U.S. intelligence agencies have concluded that Russia interfered in the final stretch of the presidential campaign to help Trump win the presidency, and not simply meddle in the U.S. electoral process as previously thought, according to senior administration officials. The conclusion was based to some extent on a finding that Russians had hacked the Republican National Committee's computer systems, in addition to those of Democratic organizations, but had leaked material only from the Democrats on WikiLeaks.

Tillerson also met privately with the president-elect on Tuesday, after recommendations from former Secretary of State Condoleezza Rice and Defense Secretary Robert Gates. A transition official said Trump was impressed with Tillerson's style and experience.

Other contenders for secretary of state are said to include former U.N. Ambassador John Bolton, Senate Foreign Relations Committee Chairman Bob Corker, former Ford Motor Company CEO Alan Mulally and retired Navy Admiral James Stavridis.

Giuliani withdrew his name from consideration as Trump broadened his search for the nation's top diplomat. Giuliani received strong support from political outsiders who are close to Trump. But his Senate confirmation would have been questionable because of conflict-of-interest concerns related to work his consulting business did on behalf of foreign governments.

"Rudy Giuliani is an extraordinarily talented and patriotic American," Trump said Friday in a written statement. "I will always be appreciative of his 24/7 dedication to our campaign after I won the primaries and for his extremely wise counsel."

Trump said he would continue to seek Giuliani's advice after he assumed the presidency.